People on Social Media Drink a Gallon of Water a Day—How Much Water Do You Really Need?

Staying hydrated is important, and there are many people on TikTok and other social media platforms preaching that you need to drink a gallon of water a day, or 4.5 liters, in order to achieve adequate hydration.

The hashtags #gallonofwateraday, and #cirkul have garnered millions of TikTok views, and the latter hashtag refers to a normal-looking water bottle with an intensity-adjustable water-flavoring mechanism to stimulate drinking.

But how much water do we really need to drink each day?  The U.S. National Academies of Sciences, Engineering, and Medicine say an adequate daily intake of fluid is about 3.7 liters for men, and 2.7 for women.

You should also keep in mind that about 20 percent of our daily fluid intake comes from food. So after accounting for this, Dr. Michael Daignault says we should aim to drink about six to eight glasses of water a day (1.2-1.5 liters.), and higher amounts are needed for athletes, those who live in hot or humid climates or at high altitudes, and those sick with fever, vomiting, or diarrhea.

He also says a good metric to follow is based on observable signs that your body is telling you it has had enough water—one of those measures is the color of your urine, if it’s pale-yellow in color you are adequately hydrated, while if it’s too dark or clear, you’re dehydrated or over hydrated.